Brushcutters are known per se and include a protective tube which is either straight or bent. The cutterhead of the brushcutter is carried at one end of the tube and the drive member at the other end thereof. The drive shaft connects the motor to the cutterhead and is supported in the protective tube by at least one bearing sleeve unit. For this purpose, the bearing sleeve unit includes radial holding ribs which extend in the longitudinal direction of the protective tube.
No significant tolerance differences are permitted to occur when the bearing sleeve unit is built into the protective tube. If the bearing sleeve unit is undersized, then the support ribs do not lie radially against the protective tube so that an adequate support of the drive shaft within the protective tube is hardly provided. If the bearing sleeve unit is oversized, then inwardly directed forces acting radially on the support ribs can occur when building the bearing sleeve unit into the protective tube. These forces can deform the bearing sleeve unit and considerably limit its bearing characteristics. Especially in the case of bent protective tubes, an increased radial force can be applied to the bearing sleeve unit because an oval cross section is imparted to the protective tube in the bent region thereby causing the bearing sleeve unit to become deformed thereby causing its bearing characteristic to deteriorate. The drive shaft rotates in the bearing sleeve unit at a rotational speed of 7,000 rpm and more and generates a considerable friction heat whereby damaging excessive temperatures can develop in the bearing sleeve unit especially in the deformed region of the protective tube.